Two academic years ago I began teaching at a first level university in a provincial capital. I located the position by sending my resume to the FAO department's email address, displayed prominently on their English website. I was interested in this city for a variety of reasons: climate, air quality, transportation etc. The new university easily negotiated and acquired the release documentation from my prior employer. I received offers from two other universities, one in Kunming and one in Nanchang.
When I arrived in my FT housing in August, I found the teaching materials, contract and work schedule of the teacher I was replacing on the apartment computer and in the cabinet.
Long story hopefully short, my contract called for 14 hours a week at a salary of 8000, plus 2000 each month if I chose to teach an additional 4 hours a week.
The teacher I replaced (and an another Italian guy who is still teaching English) were supplied by an agency. The woman I replaced, from the Philippines, was teaching 30 hours a week, 24 teaching hours for a base salary of 4000 and 2000 for 6 hours in overtime.
For 4000 rmb less a month, the university was receiving 12 additional teaching hours than I provided.
I am not aware what the agency fee was to the University.
The agency no doubt lost its University client because of 2015 increased government scrutiny on non-NES teachers. The Italian guy, who was teaching English, had a contract to teach Italian. He was, of course, subject to deportation at any time if anyone reported him, so I will not identify the University.